I'm presently writing a setting sourcebook for my own campaign, and I'd like it to look at least somewhat like the D&D 5e books, but I'm finding most of the obvious software programs used for writing documents like this fall well short.
What software programs the WOTC design team uses to layout the D&D 5e core rulebooks?
I'll give an example. I was playing around in Apple's Pages app. I was trying to set one page as a two column layout, but then have the next page be a 3 column layout with an image in the middle of the page. I eventually got it to work, but it involved going through a series of like 50 steps and lots of obscure settings. After flipping through the D&D core rule books, and seeing the various pages have so many different layout (one, two, three columns, images all over the pages, multiple fonts and typfaces...) I can't imagine that they'd be using something like Pages to do that kind of work.
I tried with MS Word, OpenOffice and Google Docs too, all with varying degrees of success and failure. What does WotC use?